Filtering device for precisely controlling an intensity distribution of light beam

摘要

An absorption type continuous neutral density filter controls an intensity distribution of a light beam from a laser to provide the intensity distribution of the light beam desired by an user. In the filter, the intensity distribution of the light beam is controlled by adjusting absorption of the light beam by the varying thickness of medium of the filter. This control of the distribution of the light intensity is accomplished by predefining the variance of thickness of the filter to a form required by the user. As a result, the continuous neutral density filter can be easily fabricated.